The Ottawa Senators have surprised again.

Eliminating the Boston Bruins on Sunday, the Senators advanced to the second round of the postseason for a date against the New York Rangers.

It marks the first series win for the Senators since 2013 and just their second since 2007, the same year they made it all the way to the Stanley Cup Final.

This season, the Senators have been one of the most consistent clubs, never losing more than twice in a row as the team has continued to achieve away from the limelight. Three key reasons stand out for the Senators' success:

Craig Anderson

The Senators netminder doesn't garner the headlines like the league's bigger names, but his stat line certainly speaks to his performance.

Missing most of the season due to a leave of absence to be with his ill wife, Anderson made his permanent return to the crease in mid-February. From that point, he wrapped up the regular season with a 13-5-3 record and a .929 save rate. Only Jake Allen posted better numbers than Anderson with as many appearances over that stretch.

Anderson's play has carried through to the postseason, where he shut the door and outdueled Boston netminder Tuukka Rask:

The Senators hope Anderson can put up a similar performance in Round 2 versus the Rangers.

Boucher's Balanced Attack

The Senators' forward ranks is without a superstar, but the team's offensive arsenal still has a few choice weapons.

This season, three Ottawa forwards - Mark Stone, Kyle Turris, and Mike Hoffman - broke the 50-point plateau, and all three also potted at least 20 goals.

In all, Ottawa's scoring value comes in spades: 10 Senators reached double-digit tallies this season, including Derick Brassard and Bobby Ryan, who proved invaluable in the opening-round series against the Bruins, combining for 15 points in the six-game set.

It's a balanced attack that fits perfectly with the style of first-year coach Guy Boucher, who preaches a defensive approach that finds its opportunities in exposing the opponent's mistakes.

Erik Karlsson

You can't stop Karlsson, you can only hope to contain him.

The play of the Senators captain isn't a secret, but it's no doubt a force. Shutting down a superstar is a key focus of any coach, and that's no different when facing the Ottawa defenseman.

Already a two-time Norris Trophy winner, Karlsson is once again in contention as the league's top defenseman. Not only did Karlsson put up 71 points on the season, he was effective at both ends of the ice, finishing second in the league with 201 blocked shots.

His highlight-reel plays have carried through to the offseason, with Karlsson already putting together a few jaw-dropping plays:

Now up against New York, Karlsson will have a chance to make that music before a Broadway audience.

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